Not sure who invented the Helical, but I first saw it in On Rope. Then saw it in a knot book labeled the Penberthy. The big difference between it and the other hitches being discussed is it has a single eye.
The hitch in CurSed's picture is the French Prusik, typically five or more wraps and one crossing, or braid in the back. There is a similar hitch, the Autoblock, that is all wraps and no braid in the back.
The function of the VT depends largely on the length of the eye legs, as Burham stated. There is a slight difference on how the first braid is made, but it would only come into play if the legs were too long. In Mugg's video, I'm not sure that last braid in front does anything friction wise. Using two braids with much shorter legs would be better, I think.
Yeah, I'm one bored climber, treetx.